Black Sponge Crab (Oregonia sp.)

Black Sponge Crab The Saltwater Black Sponge Crab is a perfect crab for a reef tank as it helps propagate soft corals through the aquarium. They generally decorate their shells with algea, soft corals, or sponge as a method to camoflauge themselves. The Saltwater Orange Sponge Crab is a nocturnal crab and hunts at night.